'use strict';


var db = require('../database');
var plugins = require('../plugins');
var async = require('async');

var rewards = module.exports;

rewards.checkConditionAndRewardUser = function (uid, condition, method, callback) {
	callback = callback || function () {};

	async.waterfall([
		function (next) {
			isConditionActive(condition, next);
		},
		function (isActive, next) {
			if (!isActive) {
				return callback();
			}
			getIDsByCondition(condition, next);
		},
		function (ids, next) {
			getRewardDataByIDs(ids, next);
		},
		function (rewards, next) {
			filterCompletedRewards(uid, rewards, next);
		},
		function (rewards, next) {
			if (!rewards || !rewards.length) {
				return callback();
			}

			async.filter(rewards, function (reward, next) {
				if (!reward) {
					return next(false);
				}

				checkCondition(reward, method, next);
			}, function (eligible) {
				if (!eligible) {
					return next(false);
				}

				giveRewards(uid, eligible, next);
			});
		},
	], callback);
};

function isConditionActive(condition, callback) {
	db.isSetMember('conditions:active', condition, callback);
}

function getIDsByCondition(condition, callback) {
	db.getSetMembers('condition:' + condition + ':rewards', callback);
}

function filterCompletedRewards(uid, rewards, callback) {
	db.getSortedSetRangeByScoreWithScores('uid:' + uid + ':rewards', 0, -1, 1, '+inf', function (err, data) {
		if (err) {
			return callback(err);
		}

		var userRewards = {};

		data.forEach(function (obj) {
			userRewards[obj.value] = parseInt(obj.score, 10);
		});

		rewards = rewards.filter(function (reward) {
			if (!reward) {
				return false;
			}

			var claimable = parseInt(reward.claimable, 10);

			return claimable === 0 || (userRewards[reward.id] < reward.claimable);
		});

		callback(null, rewards);
	});
}

function getRewardDataByIDs(ids, callback) {
	db.getObjects(ids.map(function (id) {
		return 'rewards:id:' + id;
	}), callback);
}

function getRewardsByRewardData(rewards, callback) {
	db.getObjects(rewards.map(function (reward) {
		return 'rewards:id:' + reward.id + ':rewards';
	}), callback);
}

function checkCondition(reward, method, callback) {
	method(function (err, value) {
		if (err) {
			return callback(err);
		}

		plugins.fireHook('filter:rewards.checkConditional:' + reward.conditional, { left: value, right: reward.value }, function (err, bool) {
			callback(err || bool);
		});
	});
}

function giveRewards(uid, rewards, callback) {
	getRewardsByRewardData(rewards, function (err, rewardData) {
		if (err) {
			return callback(err);
		}

		async.each(rewards, function (reward, next) {
			plugins.fireHook('action:rewards.award:' + reward.rid, { uid: uid, reward: rewardData[rewards.indexOf(reward)] });
			db.sortedSetIncrBy('uid:' + uid + ':rewards', 1, reward.id, next);
		}, callback);
	});
}
